Chassis Grounding - Juniper M10i Hardware Manual

NOTE: We recommend that you provision at least 13.5 A @ 48 VDC and use a
facility circuit breaker rated for 15 A minimum. Doing so enables you to operate the
router in any configuration without upgrading the power infrastructure, and allows
the router to function at full capacity using multiple power supplies.

Chassis Grounding

To meet safety and electromagnetic interference (EMI) requirements and to ensure
proper operation, the router must be adequately grounded before power is connected.
Power consumption for minimum configuration:
Base system + 1 CFEB + 2 HCMs + 1 Routing Engine + 1 PIC =
0.7 A + 1.4 A + 2(0.2 A) + 0.625 A =
0.7 A + 1.4 A + 0.4 A + 0.625 A = 3.125 A @ 48 V = 150 W DC
Power consumption for maximum configuration:
Base system + 2 CFEBs + 2 HCMs + 2 Routing Engines + 8 PICs =
0.76 A + 2(1.4 A) + 2(0.2 A) + 8(0.625 A) =
0.7 A + 2.8 A + 0.4 A + 5 A = 8.9 A @ 48 V = 427.2 W DC
Input current from a DC source other than 48 V (based on maximally configured
router; applies to DC power supply only):
(54 VDC input) x (input current X) = (48 VDC input) x (input current Y)
54 x X = 48 x 8.9 A
X = 48 x 8.9 A / 54 = 7.9 A
System thermal output for maximally configured AC-powered router:
Watts DC/65% AC PEM efficiency/0.293 = BTU/hr
427.2/0.65/0.293 = 2243 BTU/hr
System thermal output for maximally configured DC-powered router:
Watts DC/0.293 = BTU/hr
427.2/0.293 = 1458 BTU/hr
Appendix C: Power Requirements, Guidelines, and Specifications
Power Guidelines, Requirements, and Specifications
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